Somatic cells can be induced to generate pluripotent stem cells that functionally resemble embryonic stem cells (ES cells). This reprogramming process, rooted in the remarkable cellular plasticity retained during differentiation, can be triggered by exogenous expression of a set of ES-cell specific gene regulators. However, reprogramming occurs with low efficiency and slow kinetics using the current technologies, reflecting our lack of in-depth mechanistic understanding of this process. At present, among the best-characterized reprogramming factors are a defined set of transcriptional regulators, Oct4 and Sox2, Klf4 and c-Myc. Most of these factors constitute integral components of the core gene regulatory circuits that coordinately control pluripotency and self-renewal in pluripotent stem cells.
miRNAs are a large family of small non-coding RNAs that primarily repress gene expression by pairing with partially complementary mRNA targets. The small size of miRNAs, combined with their imperfect target recognition, gives them enormous capacity and versatility to regulate global gene expression. miR-34 miRNAs belong to an evolutionarily conserved family. In mammals, there are three homologous members, miR-34a, b and c, which are localized to two distinct genomic loci, mir-34a, and mir-34b/c.
There is a need in the art for methods of generating induced pluripotent stem cells.
Literature
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